Abstract
To the Editor:
We read with great interest the article by Lieba-Samal et al. “Field testing of ICHD-3 beta criteria of periictal headaches in patients with focal epilepsy.” The authors found that 75.7% of episodes of periictal headache do not meet the criteria of ICHD-3 beta, mostly because of the preictal onset of the headache (1). According to these criteria, the periictal headaches are defined as “7.6 headache related to an epileptic seizure, 7.6.1 hemicrania epileptica or 7.6.2. postictal headache”, there is no criterion for preictal headaches (2).
The study by Lieba-Samal was conducted in an adult population, whereas we studied the periictal headache in school-age children. In our prospective study, we selected 57 patients with periictal headache from the population of children with epilepsy (aged 6–18), and followed them up prospectively. Parents completed the 180-day seizure and headache diary.
The postictal headache and ictal headache (hemicrania epileptica) were classified according to ICHD-3 beta criteria. The preictal headache (according to the definition used in literature) was defined as appearing within 24 h before the seizures and lasting until the seizure onset.
The observation time in our study was twice as long as in the Lieba-Samal study. The total number of recorded seizures were 913. Postictal headaches appeared in 23.44%, ictal in 3.9% and preictal to 8.21% of seizures. Preictal headaches were most frequently related to primary generalized tonic-clonic seizures.
It should be emphasized that it can be difficult to distinguish the ictal headache from the preictal headache (especially short-lasting preictal headache) without a simultaneous EEG. In our study, the duration of preictal headache varied from 30 minutes to 4 hours and occurred as early as 30 minutes before seizure onset. We suppose that a headache duration of at least 30 minutes indicates the diagnosis of preictal headache.
According to data from the Lieba-Samal analysis and our outcomes, preictal headaches exist and they are probably one of the prodromal symptoms of the seizure. More studies are needed to establish the prevalence of preictal headaches and to develop relevant criteria.
Footnotes
Declaration of conflicting interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The authors received no financial support for the research, authorship, and/or publication of this article.